It is known in modern motor vehicles to provide one or more sensors which continuously provide data which can be used to detect objects in the vicinity of the vehicle. Suitable sensors include cameras (which may detect optical wavelength of light, or other wavelengths, such as infrared), ultrasonic detectors, or radar/lidar. Data from the sensors may be processed by one or more on-board vehicle processors to make determinations about objects near the vehicle. Objects of interest include other road users, for instance pedestrians, cyclists or animals, and also fixed or inanimate structures, such as lamp posts, trees and obstructions in the road.
A vehicle's on-board processors may further make a determination as to the relevance of an object, by which is meant the potential importance of the object to the driver of the vehicle. An evaluation as to the relevance of an object may be made depending on the type of the object (i.e. whether the object is human or a tree), or on the position of the object relative to the vehicle or relative to surrounding features (e.g. whether an object is on the road, on an adjacent pavement, or on a pedestrian crossing). The absolute movement of the object as well as the movement of the object relative to the vehicle, may also be taken into account when a evaluating the relevance of the object.
When an object has been classified as being relevant, its movement may be followed, and further readings will be taken with respect to the object to determine whether the relevance of the object changes. For instance, if an object is classified as being a pedestrian who is on the road ahead of the vehicle, then the relevance of the object is likely to be judged to be high. However, if the pedestrian moves to a pavement and is no longer in the path of the vehicle, the relevance of the object will be reduced.
In some vehicles, a video camera is used, and an image of the road ahead of the vehicle may be displayed to the driver. In such circumstances, objects which are classified as being relevant may be highlighted in the image which is displayed to the driver, to draw the driver's attention to the object.
It is an aim of the present invention to seek to provide an improved system of this type.
Accordingly, one aspect of the present invention provides a system for detecting objects in the vicinity of a vehicle, comprising: a sensor for gathering data relating to objects in the vicinity of the vehicle; and a processor operable to: detect objects, from the sensor data, based on one or more detection criteria, the detection being regulated by one or more detection parameters; analyse the detected objects; and in response to the number of detected objects, vary one or more of the detection parameters.
Advantageously, the sensor comprises a video camera.
Preferably, at least one of the detection parameters comprises a threshold relating to the angular size of an object appearing in data gathered by the sensor.
Conveniently, at least one detection parameter relates to the distance of the object from the vehicle.
Advantageously, at least one detection parameter relates to the contrast between the object and its background.
Preferably, at least one detection parameter relates to the position of the object with respect to the vehicle.
Conveniently, the detection parameter relates to the angular distance of a line joining the vehicle and the object from the trajectory of the vehicle.
Advantageously, at least one detection parameter relates to the type of object that is detected.
Preferably, at least one detection parameter relates to an estimated probability that the object is of a specific type.
Conveniently, at least one detection parameter relates to the application of a filter to an image or other data gathered by the sensor.
Advantageously, the application of the filter smoothes out small features in the image or other data.
Preferably, a preferred number of detections is defined for a set of data gathered by the sensor; and the at least one detection parameter is varied so that the number of detections produced using the detection parameters for a subsequent set of data is close to the preferred number.
Conveniently, the derivative of the number of detections with respect to variation of at least one of the detection parameters is determined.
Advantageously, detected objects are analysed by a classifier which is trained through analysis of a large number of known objects.
Preferably, detected objects are analysed to reach a determination as to whether the vehicle is likely to be involved in an impact with the objects.
Conveniently, if it appears that the vehicle is likely to be involved in an impact with one of the objects, a vehicle safety system is activated.
Advantageously, the system further comprises a display on which at least some data gathered by the sensor is displayed to a vehicle occupant.
Preferably, objects that are determined to be potentially relevant are highlighted in the display.
Conveniently, detected objects are classified by a classifier having two or more classification steps.
Advantageously, a first classification of the two steps is regulated by one or more classification parameters, and one or more of the classification parameters is varied in response to the number of objects classified in the first classification step.